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排序方式: 共有651条查询结果,搜索用时 15 毫秒
61.
WANG Zhi-xin HOU Yi HAN Wei WANG Kai-chen GUO Bao-feng LIU Ying CHANG Xi-hua WANG Wei-hua NA Wan-li KONG Xiang-bo ZHAO Xu ZHANG Ling 《高等学校化学研究》2011,27(1):94-98
Renal cell carcinoma is the most common cancer of the kidney, and resistant to traditional therapies. The aim of this study is to investigate the effects of hydroxyapatite nanoparticles on human renal cell carcinoma 786-0 cells. Cell proliferation was assessed with an 3-(4,5-dimethylthiazol-2-yl) 2,5-diphenyltetrazolium bromide(MTT) staining kit. The apoptosis assay was assessed with an FITC Annexin V Apoptosis Detection Kit. Caspase-3 and caspase-12 were detected by immunocytochemical staining and semi-qua... 相似文献
62.
Marks JR Placone J Hristova K Wimley WC 《Journal of the American Chemical Society》2011,133(23):8995-9004
Combinatorial peptide chemistry and orthogonal high-throughput screening were used to select peptides that spontaneously translocate across synthetic lipid bilayer membranes without permeabilization. A conserved sequence motif was identified that contains several cationic residues in conserved positions in an otherwise hydrophobic sequence. This 9-residue motif rapidly translocates across synthetic multibilayer vesicles and into cells while carrying a large polar dye as a "cargo" moiety. The extraordinary ability of this family of peptides to spontaneously translocate across bilayers without an energy source of any kind is distinctly different from the behavior of the well-known, highly cationic cell-penetrating peptides, such as the HIV tat peptide, which do not translocate across synthetic bilayers, and enter cells mostly by active endocytosis. Peptides that translocate spontaneously across membranes have the potential to transform the field of drug design by enabling the delivery of otherwise membrane-impermeant polar drugs into cells and tissues. Here we describe the chemical tools needed to rapidly identify spontaneous membrane translocating peptides. 相似文献
63.
HAI QING LIU LI NA ZHANG AKIRA TAKARAGI TAKEAKI MIYAMOTO 《Cellulose (London, England)》1997,4(4):321-327
The effect of substituent distribution on the water solubility of O-methylcellulose (MC) was re-examined to elucidate the
lower limit of the degree of substitution (DS) in water-soluble MC. To this end, a series of 2,3-MCs which are regioselectively
substituted at the C-2 and C-3 hydroxyl groups were prepared by homogeneous methylation. It was found that the lower limit
for the DS value of water-soluble 2,3-MC was almost the same as that for MCs having even distributions of substituents along
the cellulose chain as well as in the anhydroglucose units.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
64.
R. S. Addleman M. J. O’Hara T. Marks J. W. Grate O. B. Egorov 《Journal of Radioanalytical and Nuclear Chemistry》2005,263(2):295-300
Summary The determination of transuranic (TRU) content in nuclear wastes, reactor materials, process solutions, and various other matrices is required in support of material assessment, environmental restoration, and waste processing activities. We have found that direct measurement of TRU is possible using surface passivated ion implanted planar silicon diode detectors. The performance and durability of modern silicon diodes enables direct detection of alpha-particles, with retention of some spectral information, through small air gaps or under direct contact with liquid or solid samples. We will present results on the performance of silicon diode detectors for the determination of TRU in liquids. 相似文献
65.
Maurice J. Marks Nikhil E. Verghese K. James Hrovat Anamari Laboy‐Bollinger James C. Buck James A. Rabon Jr. Carol L. O'connell Lisa Allen 《Journal of Polymer Science.Polymer Physics》2008,46(15):1632-1640
Five families of new controlled epoxy thermosets (CENs) using three monophenol chain terminators were prepared to study systematic changes in the structure and amount of the monophenol and the initial molecular weight between crosslinks (Mc,i) on the properties of epoxy thermosets. Glass transition temperature (Tg) decreases with monophenol mole fraction (χ) in proportion to both the concentration and flexibility of the chain terminator. Distinct serial relations for Tg depression were observed for the three Mc,i families. Dynamic mechanical analysis (DMA) shows significant perturbations of the relaxation behavior with added terminator as evidenced by decrease in peak tan δ and in post Tg damping. The rubbery coefficients of thermal expansion (CTE) increases with monophenol concentration only at χ > 0.05 and shows distinct curvature versus temperature, but is largely invariant with monophenol flexibility. The thermal stability of terminated CENs decreases only slightly with χ and little difference was found with monophenol structure. Most surprisingly, fracture toughness decreases markedly and discontinuously with χ depending on Mc,i. The values of the critical monophenol concentration at which fracture toughness markedly decreases (χc) are inversely proportional to Mc,i but are independent of monophenol flexibility. No correlation of χc with any of the calculated network structure parameters was apparent. © 2008 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 46: 1632–1640, 2008 相似文献
66.
Inabe T Gaudiello JG Moguel MK Lyding JW Burton RL McCarthy WJ Kannewurf CR Marks TJ 《Journal of the American Chemical Society》1986,108(24):7595-7608
67.
J. Badier J. Boucrot J. Bourotte G. Burgun O. Callot Ph. Charpentier M. Crozon D. Decamp P. Delpierre P. Espigat B. Gandois R. Hagelberg M. Hansroul Y. Karyotakis W. Kienzle P. Le D? J. Lefran?ois Th. Leray J. Maillard A. Michelini Ph. Mine G. Rahal O. Runolfsson P. Siegrist A. Tilquin J. Valentin R. Vanderhaghen S. Weisz NA Collaboration 《Zeitschrift fur Physik C Particles and Fields》1981,11(3):195-202
From π- interactions at 150 GeV/c on a heavy target, we present the final analysis of the dimuon decay angular distribution in the mass interval 4.5–8.5 GeV/c2. Results are presented and discussed in various reference frames and are also given in terms of the density matrix elements. Finally the possible contribution of higher-twist effects at largex 1 is discussed; we find that our data are not compatible with higher twist contributions as proposed by the Berger and Brodsky Model. 相似文献
68.
69.
M. C. Abreu M. Alimi C. Baglin A. Baldit G. P. Barreira M. Bedjidian P. Bordalo S. Borenstein J. Britz A. Bussiere P. Busson A. Casaca R. Cases J. Castor C. Charlot B. Chaurand D. Contardo E. Descroix A. Devaux J. Fargeix X. Felgeyrolles P. Force L. Fredj J. M. Gago C. Gerschel P. Gomes P. Gorodetzky J. Y. Grossiord A. Guichard J. P. Guillaud R. Haroutunian L. Kluberg L. Kraus G. Landaud I. Linck C. Louren?o A. Maio L. Peralta M. Pimenta J. R. Pizzi C. Racca S. Ramos A. Romana R. Salmeron A. Sinquin P. Sonderegger J. Varela NA Collaboration 《Zeitschrift fur Physik C Particles and Fields》1988,38(1):129-133
The like-sign dimuons copiously recorded in the NA 38 experiment both inp-U and O?U reactions at 200 GeV/nucleon are interpreted as resulting from decays of π andK mesons in comparable proportions. The ++/?? ratio is large (?1.7) and ascribed to theK + being more copiously produced than theK ?. Both the average transverse momentum and the ++/?? ratio are comparable forp-U and O?U reactions, and both increase only slightly with the transverse energyE T . 相似文献
70.